Improve



zsheerssheezz. E. ERA Y. Electric Teieg raph for Trafismiiting M u sia N0. I66,095.

ai Tun es. 'Patentedjuly 27,1875.

hllTiZiU hl'mzrhc n which ELISHA GRAY, on CHKGAGO, lnmnoish IMPROVEMENT lie! ELECTlilC TELEGRAPHS FOR TRANSMHHNQMUSQCAL. TUNE? Specification forming part of Letters Patent No. cocoon; flatd July 27, 1875; applicntiou filed January .To 'all whom it may concern.-

Be it known that ELISHA GRAY, of Chihcogo, in the county of Cool; and State of Illi nois, have invented a certain new and uceful Apparatus for Tronsmitting Musical Imprcssions or Sounds Telographicaily, of which I hereby lloclsrc the following to he a full, clear, and exact description. Y

Myinvcntion relates to What 1 term van electro-hnrmonic telegraph, and is based upon the fact well known to electricians that an electromagnet clongotes 'under the action of the electric current, and contracts again'whcn the cur rent ceases. Consequently a succession of impulses or interruptions will canoe the magnet to vibrate, and if those vibrations he of sufii: cicntfrequencyc musical toncwill hc prodnccfi, the pitch of which will Gopcnt'lupon the rapidity of the vibrations .I have discovered that by interrupting on electric current at the transmitting and of a line with sufficient frequency to produce a. musical tone by an instrument vibrated by said interruptions, and transmitting the impulses thus induced to an clcctro-magnct at the receivingcnd of the line, the latter will vibrato synchronously with the transmitting-instrument, and thus p'rmlucc a, musical tone or note of a corresponding pitch. 'lhc ohjcct of my invention in to utilize this discovery for the transmission of intelligible signals to adistancc by electricity; to which. cod my improvement, consists in the combination of a telegraphic circuit, a ocrics oi ciz'=(n1il;-l)reohe1's capable of producing musical tones of ciii'crcnt pitch, a sorics of keys for simultaneously or succesoi vcl y throwingsnici circuit-breakers intooront of operation,'and on clectro-mognct rcccivcr, which is thrown intoopcrotion by the transmittcr, whereby tones of difi'ercni: pitch may be reproduced at the receiving end of the line by the use. of a single circuit.

In tho accompanying drawings, Figure 1 shows a plan view of the trzthcniitting port of my improved apparatus the receiver appearing in perspective. Fig. 2 is a. View, in pen spcctivc, of the transmitter,

The transmitting apparatus is mount-nil npon n baseboard, A,ns cocci. The induction-coil B has tho usual primary curl nccominry cir cults. An orsiinziry automatic clcctrotomc, 0;

has a circuit-closing Spring, 0, so adjusted As, when in action, to produce a musical tone according to its Length, thickness, and adjusttext/cooling through two or more octaves may he produced. An ordinary electromagnet is provided at the receiving and of the line.

The operation of the apparatus is'a-s follows: In the arrangement shown in the drawings.

when a key is closer the primary circuit will pass from the battery H through that kcyan d its corresponding electro'toinc nd willbeautomaticolly interrupted in the usual manner-L The spring of the elcctrotome will thus ho caused to vibrate rapidly and to produce :a

tone, the pitch of which is determined by' the rate of vibration. It is obvious that several keys may be depressed si znultancously. These vibrationsor interruptions of the current will simultaneously produce in the secondary circuit of the induction-coil a series of induced currents or impulses corresponding in number with the vibrations of the electrotome, and as the receiving clectro-magnet is conhcctcd with this circuit it will be caused to' vibrate, thus prmlncing a tone of corresponding pitch tho sonnet of which may he intensified bythc 22cc oil a. hollow cylinder, 5,05 metal, placcdou poles of the magnet 'When a singlc clcctrotomc is thrown into action, he correspohding tone will be repro dncerl on than Index by the magnet. When electrotomcs (lifi'crent pitch are successively operated, their tones will. be correspondingly rcproiluced by the'recciver, and when two or more clccti'otomes'arc simultaneously sounded thctono of each will still he reproiluced with-- out confusio on thc soundcr,oy whichimcans I am cnoblerlto reproduce xncloflico or tunes,

Mcchanica circnithreakcro might be sub-- ntitntcai for the zintomatic vibrating electrotome, hercinhcforc described, and I have, in

feet, used such mechanical circuit-breakers of various constructionybiil; I fonnfii the elective tome nloreeetisfecioryin practice,

In this insizence the receiver is shown and. described as operated by the influcefi current of the seoomiery coil; but the secondary 0i. extra. current of a primary coil may be used insteadthereof with good efi'eot.

My apparatus is. specially adeptefl no Sela graphing on long land and submarine lines By it let ters and signals can be repreeenteii by tones differing in pitch; or the ordinary Morse signele can be made by eliortfend long interruptions in a prolonged tone of me some pitch, thus securing great rapidity of transmission.

.An application for Letters Patent'of like United States, filed'hy me April 18, 1674, shows an apgaratus somewhat eimilar to the one herein described, for transmitting musical tones through animal tissue to a resonant electrieal receiver. I do 110b,thGI'GfOIGfilillHlhfii'Q- ineinything-therein shoyvm Neither do I claim herein the combination, with e main line, of an. intermittent; circuit breaker; or a series thereof, each adapted io'throw upon the line s;- definibe number of electricel impulses per nnii: of time, and a Key or keye, one for semi controlling eaohsnoli oiremit-breekezyaeit' eon stitutes the subjeobmetiei" of another application filed by me February 23 1875.. The combination of a telegraphic oireuib en swim metic circuit-breaker capable of pi'ofinoing e, mueioal tone, and an eleetro-mognei receiver whioii reproduces the tone by being iiizirown iuio vibration by imyu'isee generated by die circeib-broak or, is not broaeily, eleimed herei o, z 7

as this combination eonefiiiutee e @3105; of the subjeciz-nietter of said appliombion also.

I claim as my own invention- The oombineiion of e telegraphic ci vouie, a,

' musical tones of different pitcmeeeries of keys for simultaneously 0i successively throwing said eircu'il;-breekere into or oub of opereiion andanelectro-magnetreoeiveiywliichiethrown into operation by the iransmittei's, whereby .tones of difiei-ennpitoh may be ireproduced iii 1 the receiving;- end of the line by the empioyment of a single eii'euim .ELE'SHA. GEAYL Witnesses:

E. C. Diwizoson, W'M. J. PEFZION. 

